Selective two-speed brace



A. w. CLARK sELEc'rIvE Two-SPEED BRACE med May 17 194s Patented Aug. 29, 1950 UNIT STTS

SELECTIVE TWO-SPEED BRACE Ancel W. mark, Qakland, Calif.

Application May i7, 1946, Serial No. 670,397

8 Claims. 1

My invention relates to braces, drills and similar devices used in connection with rotary tool members, generally referred to as angers for boring holes in wood, drills for metals and the like, screw-driver bits for driving and removing screws, and socket wrenches for unscrewing or screwing cap screws or nuts. All of these various selective types of tools can be used with a conventional drill or brace chuck with any conventional brace or drill. Though adaptable to breast drills and the like, the greatest utility of my invention exists in connection with the conventional carpenters brace which is conventionally capable of operating at only unit ratio.

My invention provides selective and instantaneous conversion of a brace between unit and multiple ratio, in conjunction with conventional forward and reverse ratchet means but with the ratchet means operative for both, high and unit ratio, for either forward or reverse, or with no ratchet action for high ratio, as may be desired. depression of a single button by a finger of the hand holding the brace head converts the chuck to sweep ratio from unitary to multiple, and release of the button changes the brace back to unit ratio. For selective forward, reverse, and no ratchet action, a manually operative member is adjustable to three positions.`

The conventional brace rotates the auger or bit at the same speed as that of the sweep or crank, and when operations are to be carried on in a corner, the sweep can only be moved through a small angle, in some cases as little as l5 to 60, making the boring of holes, the driving or removal of screws or nuts a very slow and tedious operation.

With my invention this small movement of the sweep is multiplied to provide double or` triple the degree of motion to the rotary tool, and the speed of operation is thus increased more than the ratio would indicate because of the more ellicient operation through a greater arc and the lack of lost motion in making two` or three swings of the sweep to accomplish what the single sweep does when my invention is used.

The objects and advantages of the invention are as follows:

1First, to provide a selective two-speed brace.

Second, to provide a selective two-speed brace which is instantly convertible from unit to multiple ratio, at will.

Third, to provide a brace of the type outlined` which is convertible to a ratchet type for forward, reverse, or no ratchet, and for either unit or muh tiple ratio.

Fourth, to provide a brace of the type outlined which normally operates at unit ratio and is convertible to multiple ratio simply by depressing a member on the brace head by one of the ngers of the hand holding the,` head.

to provide a brace as outlined which is simple in construction and arrangement and economical to manufacture, and which can be used with any conventional rotative tool conventionally used with a brace or the like.

In describing the invention reference will be made to the accompanying drawings in which:

Fig. 1 is a side elevation of the invention.

Fig. 2 is an enlarged view of the brace head and clutch mechanism.

Fig. 3 is an enlarged view of the speed change and ratchet mechanism.

The sweep lli is provided with relatively long radius turns l! to lil for ease of operation and reduction of friction of the flexible shaft l5 which passes axially through this hollow member, and a suitable rotatable hand grip it is provided on the sweep, this part of the invention conforming with conventional structures except as to the long radii and the internal flexible shaft. This spiral type flexible shaft can be replaced by any other type of fiexibleldriving connection such as a chain or ball-and-link type shaft or the like, all of which are well known in the art and therefore require no description.

The head Il has a form similar to the conventional brace head, and like the conventional type it is normally rotatable on the upper end of the sweep as indicated at i8, but unlike the conventional brace, this head is made in two parts, `the base le which is rotatably secured on the upper end of the sweep andbears on a collar 2D, rotatable on the journal i8 and secured by the check nuts 2 l The cap 22 is secured to the base by any suitable conventional means such as threadedly as indicated at 23. To this extent the head operates as any conventional brace head. However, a recess is formed in the base as indicated at 211 for a clutch disc 25 which on its upper face has bearing on the lower surface of y the cap as indicated at 26 and provided on the titl under side with clutching means shown as teeth 2l but which may consist of a friction facing, and is axially secured as by swedging on the terminal end 23 of the flexible shaft i5.

The finger operative engaging means is shown as consisting of a plunger 29 having a shaft 3l! extending through a bore through the base and terminating in a button 3 l 4and urged out of contact with the clutch disc by a spring 32, the upper end of the plunger having engaging means for engagement with the clutch such as a tooth 33.

The speed change mechanism consists of an internal ring gear 34 which is fixed on the other end 35 of the flexible shaft I5 and which gear has a hub 3G rotatable in a bore 3l formed axially in the lower end of the brace shaft; an arm 33 fixed on the brace shaft and carrying a planet pinion 39 which meshes with the ring gear; and a head M! which has a hub il on which is formed or` fixed a sun pinion 42 which meshes with the Iplanet pinion and which head has formed on its top surface a circular series of straight-cut ratchet teeth 43; and a chuck head 44 having an integral chuck spindle and simultaneously forming a housing for the gear train and the 3 drive for the chuck, being xed to the gear housing head as indicated at 46.

Mounted on or integral with the brace shaft 4l is a ratchet consisting of a plunger d8 having a pawl tooth 49 formed at its end for one-way ratcheting on the square-toothed ring d3, and this pawl is reciprocally mounted in a housing 5l! and urged toward the teeth 43 by a spring 5l, and this housing has a slot 52 cut low on both sides and high in the center for the adjusting lever 53 with central holding means such as a notch for retaining the pawl in a raised position as indicated in Figs. 1 and. 3, out of engagement with the teeth, and which is moved to engaging position by movement of the lever in either direction for cooperation with the teeth i3-forward for forward drive, and back for rearward drive.

The operation of the invention is as follows: With the tool such as a drill bit secured in the chuck 54, and the brace to be operated in the manner of a conventional brace, the lever 53 is moved forward toward the observer viewing Figs. 1 and 3, the brace head I1 is gripped and the sweep handle I 6 swung about the axis of the brace. The pawl i9 engages the teeth Q3 and through the head lll and housing 44 drives the chuck forward, while a reverse movement of the sweep merely ratchets back for a new pick-up.

If a higher speed is desired for the tool held by the chuck, it is merely necessary through one finger of the hand holding the brace head to depress the button 3l, which locks the clutch disc 25 to the head, and along with it locks the flexible shaft l5 to the head, while the sweep is free to be operated. The flexible shaft holds the ring gear 34 against rotation while the sweep swings the arm 38 about the axis of the shaft carrying the planet pinion with it which rotates as it moves about the interior of the ring gear, and this planet -p-inion rotates the sun pinion i2 at a speed proportionate to the ratios between the gears and pinions and in the same direction as the sweep. If for example the ring gear has 36 teeth and the sun pinion l2. the sun pinion will make three revolutions to one of the sweep, and this sun pinion through the head Il!! and housing M drives the chuck at the increased speed, the teeth merely riding from under the pawl if the pawl is adjusted to ratchet, and riding back over the teeth in a return movement of the sweep if the button 3l is released. If straight forward operation alone is required, the pawl lever should be adjusted to the position shown in Figs. l and 3 under which conditions there will be no click of the pawl or ratchet action as the brace is driven. For reverse, the lever 53 is moved back into the low portion of the rear slot under which conditions ratcheting will take place in the opposite direction of movement of the sweep.

At any time the change can be made from normal to high ratio or back to normal. To illustrate: Suppose a hole is to be drilled in a corner and that the sweep can only be operated through an angle of about 60 degrees. With the lever 53 adjusted in the low front portion of the slot, and the button 3l depressed, movement of the sweep clockwise will drive the chuck at three times the speed of the sweep or through three times the angle of 60 or 180 with a, 3:1 ratio, the teeth 43 merely riding under the pawl. Ii at the end of this movement the button 3l is released for the return movement of the sweep the flexible inner shaft will merely idle because of release of the clutch disc 25, and after this sweep movement, if the button is again depressed the drill bit will advance through another Thus, with the pawl set for cooperation with the toothed ring 43, depression and release of the button 3| changes the brace from unit to multiple speed, and if the brace is to be used at multiple speed only, then the pawl is to be adjusted in the positions shown in Figs. l and 3 out of cooperation with the toothed ring, and the button continually depressed since upon release the brace would merely idle.

I claim:

l. A brace comprising; a head and a chuck spindle and an interconnecting sweep, and means .for rotatably securing said head on one end of said sweep, and second means for rotatably securing said chuck spindle on the other end of said sweep; ratchet means cooperating between said sweep and said chuck spindle and adjustable to a plurality of positions for limiting relative rotation to either of two directions; speed changing means cooperating between said sweep and said chuck spindle; a exible shaft rotatable within said sweep and cooperating between said speed changing means and said head, and means manually operable on said head for locking said head to one end of said flexible shaft at will for changing the speed of rotation ci said chuck spindle relative to that of the sweep; said speed changing means comprising a housing integral with said chuck spindle and having an inl sun pinion, a planet pinion carried by said sweep and meshing with said sun pinion, and a ring gear connected to the other end of said :flexible shaft and meshing with said planet pinion, with said ring gear retained against rotation when said head is held against rotation and said means manually operable is operated for locking said one end of said ilexible shaft, thereby increasing the speed of the chuck spindle relative to that of the sweep in proportion to the ratio between said ring gear and sun pinion.

2. A brace comprising; a head having an axial chamber formed therein, a chuck spindle, and an interconnecting sweep, and means for rotatably securing said head on one end of said sweep, and second means for rotatably securing said chuck spindle on the other end of said sweep; ratchet means cooperating between said sweep and said chuck spindle and adjustable to two positions for limiting relative rotation to either of two directions; speed changing means cooperating between said sweep and said. chuck spindle; a flexible shaft rotatable within said sweep and cooperating between said speed changing means and said head, and means manually operable on said head for locking said head to one end of said exible shaft at will for changing the speed of rotation of said spindle relative to that of the sweep; said means manually o-perable consisting of a clutch disc rotatable within said axial chamber and having said one end of said flexible shaft axially xed thereto, and normally retracted engaging means projecting through the underside of said head and depressable at will to lock said clutch member to said head to lock said flexible shaft against rotation relative to said head.

3. A brace comprising; a hollow head, a chuck spindle, and an interconnecting sweep, and means for rotatably securing said head on one end and said chuck spindle on the other end of said sweep; ratchet means cooperating between said sweep and said chuck spindle and adjustable to two positions for hunting relative rotation to either of two directions; speed changing means cooperating between said sweep and said chuck spindle; a flexible shaft rotatable within said sweep and cooperating between said speed changing means and said head, and means manually operable on said head for locking said head to one end of said flexible shaft at will for changing the speed of rotation of said spindle relative to that of the sweep; said speed changing means including a housing integral with said chuck spin-- dle and having an integral sun pinion; a planet pinion carried by said sweep and meshing with said sun pinion, and a ring gear connected to the other end of said flexible shaft and meshing with said planet pinion, with said ring gear retained against rotation when said head is held against rotation and said means manually operable is operated for locking said head to said one end of said flexible shaft, thereby increasing the speed of the spindle relative to that of the sweep in proportion to the ratio between said ring gear and said sun pinion; said means manually operable consisting of a clutch disc rotatable within said head and having said one end of said flexible shaft axially fixed thereto; and normally retracted engaging means projecting through the underside of said head and depressable at will to lock said clutch disc to said head to lock said one end of said flexible shaft.

4. A brace comprising; a hollow head, a chuck spindle, and an interconnecting sweep, and means for rotatably securing said head on one end and said chuck spindle on the other end of said sweep; ratchet means cooperating between said sweep and said chuck spindle and adjustable to two positions for limiting relative rotation to either of two directions; speed changing means cooperating between said sweep and said chuck spindle; a flexible shaft rotatable within said sweep and cooperating between said speed changing means and said head, and means manually operable on said head for locking said head to one end of said flexible shaft at will for changing the speed of rotation of said spindle relative to that of the sweep; said means manually operable comprising a clutch member secured on said one end of said flexible shaft and rotatable within said head, and a depressable member projecting through the underside of said head and depressable at will to engage and lock said clutch member to said head and thus lock said flexible shaft against rotation relative to said head.

5. A brace comprising; a hollow head, a chuck spindle, and an interconnecting sweep, and means for rotatably securing said head on one end and said chuck spindle on the other end of said sweep; ratchet means cooperating between said sweep and said chuck spindle and adjustable to two positions for limiting relative rotation to either of two directions; speed changing means cooperating between said sweep and said chuck spindle; a flexible shaft rotatable within said sweep and cooperating between said speed changing means and said head, and means manually operable on said head for locking said head to one end of said flexible shaft at will for changing the speed of rotation of said spindle relative to that of the sweep; said speed changing means comprising a housing having said chuck spindle integral therewith and having an internal hub rotatable on said sweep, and a sun pinion on said hub; said flexible shaft extending axially through said sweep; an internal ring gear having a hub rotatable in said other end of said sweep and having said other end of said flexible shaft axially xed therein, and a planet pinion carried by said other end of said sweep and meshing with said sun pinion and said ring gear.

6. A brace comprising; a hollow head, a chuck spindle, and an interconnecting sweep, and means for rotatably securing said headV on one end and said chuck spindle on the other end of said sweep; ratchet means cooperating between said sweep and said chuck spindle and adjustable to two positions for limiting relative rotation to either of two directions; speed changing means cooperating between said sweep and said chuck spindle; a flexible shaft rotatable within sweep and cooperating between said speed changing means and said head, and means manually operable on said head for locking said head to one end of said llexible shaft at will for changing the speed of rotation of said spindle relative to that of the sweep; said means manually operable comprising a clutch member axially secured on said one end of said flexible shaft and rotatable within said head, and a depressable member projecting through one wall of said head and depressable at will to engage and lock said clutch member to said head to lock said flexible shaft against rotation with said sweep; said speed changing means comprising a housing having said chuck spindle integral therewith and having an internal hub rotatable on said sweep, and a sun pinion on said hub; an internal ring gear having a hub rotatable in said other end of said sweep and having the other end of said flexible shaft axially fixed therein, and a planet pinion carried by the lower end of said sweep and meshing with said sun pinion and said internal ring gear.

7. A brace having a sweep, a hollow head rotatably secured on one end of said sweep and a chuck spindle rotatably secured on the other end of said sweep; speed changing means cooperating between said chuck spindle and the other end of said sweep; a clutch member rotatable in said hollow head and normally retracted engaging means projecting through the wall of said head for engaging and locking said clutch member against rotation when said engaging means is manually actuated, a flexible shaft extending axially through said sweep and rotatable therein and having one end axially xed to said clutch member and the other end connected to said speed changing means; and reversible and releasable ratchet means cooperating between said sweep and said spindle for controlling the direction and speed of the spindle relative to that of the sweep.

8. A structure as defined in claim 7; said speed changing means comprising a housing integral with said chuck spindle, a ring gear having said other end of said flexible shaft axially fixed thereto, a sun pinion integral with said housing, and a planet pinion carried by the other end of said sweep and meshing with said sun pinion and said ring gear.

ANCEL W. CLARK.

REFERENCES CITED The following references are of record in the ille of this patent:

UNITED STATES PATENTS Number Name Date 1,480,231 Thompson Jan. 8, 1924 1,515,536 Armstrong Nov. 11, 1924-. 1,799,393 Rylander Apr. 7, 1931 

